Musical examples provided by: Bärenreiter Verlag

No. 4 in D minor

This piece is a typical example of how Bach's minor keys are never truly dark. Bach's D minor compositions generally depict serious aspects, as exemplified by French Suite No. 1, Sinfonia, Toccata No. 1, and The Well-Tempered Clavier Book II. In that sense, this Invention can be considered remarkably optimistic.

While the technical demands are relatively moderate, some learners may struggle with the long trills. Practice the left-hand trills especially, utilizing all possible methods to achieve speed and accuracy. If you find it difficult to play trills quickly, it might indicate insufficient fundamental muscle development; practicing exercises like Hanon could be beneficial for building strength.

As this is an enjoyable piece despite being in a minor key, all eighth notes can be played staccato, and a light, brisk tempo is appropriate. No extremely strong sections are perceived, so while the dynamic range should not be flat, extreme fortissimos are not required. A performance emphasizing elegance might be preferable.

The modulations first lead to the relative major, F major, then to the dominant minor, A minor, before returning to D minor. Vary the atmosphere in each key.

At the beginning, the music reaches B in the treble clef in measure 6, which is the highest pitched note in this piece. After reaching B in measure 6, follow the sequence, gradually decreasing volume as you descend to F in the right hand on the first beat of measure 18. Upon reaching F major, begin the trill with a soft sound. As A minor is entered in measure 26, change the atmosphere there and sustain the tension until A in measure 37.

The highest note, B, also appears twice between measures 44-45. The discussion regarding the dynamic intensity of measures 44-45 is open to interpretation. From my personal perspective as the author, I do not perceive the B in measures 44-45 as particularly loud. Rather, I feel the A in measures 36-37 to be more prominent, but this is subjective, and the performer should be free to make their own judgment.